Due to a persistent desire for a chilled beverage in remote areas frequented by outdoor enthusiasts such as hikers, hunters and fishermen, a need exists for a means to provide a light, portable, compact and quick acting apparatus to chill beverages. Numerous devices have appeared in the past in an attempt to fill this need, but appear to be impractical or so complicated in design as to be expensive to manufacture.
A search of the prior art reveals previous efforts in this field, for example: U.S. Pat. No. 2,805,556 by Wang, et al., teaches a method of chilling unbottled or uncanned beverage in a mug-like container wherein the beverage is in direct contact with a cooling evaporator. The beverage is consumed directly from the device. The device also acts to maintain the temperature somewhat while the beverage is being consumed, making it generally suitable for use by an individual person. By contrast, the present invention is used with canned beverages which are removable and any one person may consume a can of beverage while a second can is being prepared and chilled by the present invention due to the design and much greater cooling capacity.
U.S. Pat. No. 2,773,358 by Palmer, et al., shows a device for use with a beverage can. This device uses a small refrigerant cartridge which, unlike the present invention, releases the refrigerant gas under the bottom of the beverage can and does not direct the gas toward the beverage can resulting in a serious loss in cooling capacity.
U.S. Pat. No. 3,862,548 by Ladany, et al., discloses a means of releasing refrigerant gas directly into a loose liquid which is very different from the present invention.
U.S. Pat. No. 3,302,428 by Stoner, et al., teaches a chilling system wherein a liquid medium is chilled and then conducted to a beverage container, a method quite unlike the present invention.
U.S. Pat. No. 3,919,856 by Beck, et al., discloses a device wherein the refrigerant gas container is immersed in the liquid to be chilled, the container removing heat from the liquid as the expanding gases escape the container, and is substantially different from the present invention.
U.S. Pat. No. 4,054,037 by Yoder, et al., discloses a device which at first glance resembles the present invention, but which, upon further examination, differs in several important ways from the present invention. The Yoder Patent teaches the use of an expensive coil type evaporator holding the beverage can in close physical contact for heat transfer. The present invention provides a novel evaporator tube having multiple discharge openings along its length, the openings facing directly against the wall of a holding chamber. The expanding refrigerant gas is released directly against the wall allowing optimum conductive heat transfer. Further, the present invention provides the novel ejection plunger for rapid removal of the chilled can from the chilling chamber. The last two features of the present invention are not found in any of the foregoing references and serve to clearly remove the present invention from the scope of the prior art.